A method and a device for switching an inductor are described in German Patent No. 37 02 680. A coil of a solenoid valve forms an inductor. A rapid switching operation is required with solenoid valves to achieve precision fuel injection. For this purpose, energy released when the inductor is switched off is transferred to a capacitor. In a next switching operation involving the same inductor or in a switching operation involving another inductor, the stored energy causes a rapid current rise.
A disadvantage of this method is that it requires a very large capacitor, which is either very expensive or has only limited suitability for use in motor vehicles because it is neither vibration-resistant nor heat-resistant.